Relay



Dec. 16, 1924. 1,519,273

S. D. SPRONG RELAY Filed March 11, 1919 2 Sheets-Sheet 1 WITNESS S: INVENTOR /M Severn-0 5 2/0173 S. D. SPRONG RELAY Filed March 11, 1919 2 Sheets-Sheet 2 INVENTOR WITNESSES:

Sea/em D 8 9/0179 ATTORNEY Patented Dec. 16, 1924.

UNITED STATES PATENT OFFICE.

SEVERN D. SPRONG, OF NEW YORK, N, Y., ASSIGNOE TO WESTINGHOUSE ELECTRIC & MANUFACTURING CO'MPANY, A CORPORATION OF PENNSYLVANIA.

RELAY.

Application filed March 11, 1919.

To all whom it may concern:

Be it known that I, SEVERN D. Simon's, a citizen of the United States, and a resident of New York, in the county of Kings and State of New York, have invented a new and useful Improvement in Relays, of which the following is a specification.

My invention relates to relays and particularly to differential watt relays.

One object of my invention is to provide a relay that shall be adapted to control. the disconnection of electrical devices or circuits when faults obtain therein.

Another object of my invention is to provide a relay, of the above indicate-d character, that may be easily connected to polyphase devices without the necessity of phasing-out the connections.

Another object of my invention is to provide a differential polyphase watt relay that shall be adapted for use in protecting transformers the primary and secondary windings of which have different numbers of phases.

A further object of my invention is to provide a relay, of the above indicated character, that shall be simple and inexpensive to construct and effective in its operation.

In practicing my invention, I provide a movable number for controlling the tripping magnets of circuit interrupters that are located at the respective terminals of the translating device to be protected. The

movable member is actuated by a plurality of oppositely-acting watt elements that are connected at each side of the translating device. The movable member is maintained in its neutral position so long as normal conditions obtain on the translating device but,

4.0 when a fault obtains therein, one watt element will be traversed by more power than its opposing watt element or will be reversed to so assist its normally opposing element as to effect the operation of the movable magnet-controlling member and. thus cause the translating device to be disconnected from the circuit.

Figure 1 of the accompanying drawing is a front elevational view of a relay embodying my invention; Fig. 2 is a side view, partially. in section and partially in elevation,

of the relay shown in Fig. 1, and Fig. 8 is a Serial No. 281,919.

diagrammatic view of an electric system embodying my invention.

A transformer 1, having three-phase primary and two-phase secondary windings. provided with circuit interrupters 2 and for completely disconnecting the same from the circuit when a fault obtains therein. The circuit interrupters 2 and are provided with trip coils 41 and 5, respectively. that are controlled by a. difl' ercntial relay 6.

The relay 6 comprises, in general. a movable member 7 having two main armatures 8 and 9 thereon and four watt elements 10, 11, 12 and 13 that are adapted to so actuate the armatures 8 and 9 that the member 7 will be maintained in its inoperative position under normal conditions in the trans former 1.

The watt elements 10, 11, 12 and 18 severally comprise a potential winding 14., a current winding 15 and a magnetizable core member 16. The elements 10 and 11 are adapted to normally exert opposing forces on the armature 8 and the elements 12 and 13 are adapted to normally exert opposing forces on the armature 9. The windings 141- and 15 of the elements 10 and 12 are re spectively connected, through potential transformers 1'? an d 18 and current trans formers 19 and 20, to the high-tension windings of the transformer 1 to thereby cause the member 7 to develop a torque proportional to the power input into the transformer 1. Similarly the windings 1 1 and 15 of the elements 11 and 13 are respectively connected to potential transformers 21 and 22 and current transformers 23 and 24-. for the purpose of being supplied with power in accordance with the power output from the secondary windings of the transformer 1. Since the elements 10 and 11 oppose each other in their action on the armature 8 and, since the elements 12 and 18 similarly oppose each other, by adjusting two springs 25 and 26, the member 7 may be normally held in its inoperative position when normal conditions obtain in the transformer 1. That is, the springs 25 and 26 are utilized to compensate for the transformation losses in the transformer 1 to cause the opposing torques on the armatures 8 and 9 to be equal under normal conditions,

lit

A contact-carrying arm 27 mounted on the movable member I as is also an armature 28 that adapted to cooperate with manent magnet 29 to damp the nu of the member 7. A contact memh ,1 is mounted on the arm 27. adapted to eng Li e a stationary contact member for the purpose of completing a circuit 32 compri ing the winding 33 of a con ractor rela ts a source of electroanotive rorce and. the trip coils 4- and 5. lulnerg'i zation of "the winding effects engagement; of contact members 36 and to short circuit the relay contact members 30 and 31, whereby the r nit of the trip coils l and may be effectively energized, irrespective of the ettent f 'uu balance in the relay 6. That is. as soon as the contact members and 31 are engaged, the interrugters 2 and 3 will be tripped, irrespective of the oscillation of the contact member 30.

The springs 25 and 26 are provided with lever arms 38 and 39, respectively, for so adjusting the torque on the: member '7 that it shall be inoperative under normal conditions in the transforn'ier 1 but shall. permit the operation thereof when a fault obtains in the transformer. That is, when one watt element either reverses or overcomes its opposing element the member 7 is actuated to trip the interrupters.

By the use of the relay 6, effective protection may be obtained on any type of transformer, irrespective of the number of phases constituting the primary and the secondary windings thereof, and it may easily be connected to the circuits because it is not necessary to phase-out the various windings of the relay in order to obtain correct operation, as is the case in devices of this general character hereinbefore coustructed wherein the current input and output of a transformer are balanced against each other.

My invention is not limited to the specific relay illustrated or to the protection of transformers only, as it is intended to include various modifications of means for mechanically balancing the power measured at the terminals of a translatingdevice or portion of a circuit to secure protection against faults therein.

I claim as my invention:

1. The combination with an electrical translating device and protective means therefor, of a differential watt relay for controlling the protective means, the windings of the said relay being so connected to the translating device that the relay is balanced under normal conditions in the translating device.

2. The combination with a transformer and an interrupter therefor, of a movable member for controlling the tripping of the interrupter, and means connected to op-- posite terminals of the transformer for actuating the movable member in opposite directions in accordance with the power measured at the respective terminals of the transformer.

3. The combination with a two-phasethrce-phase transformer and an interrupter therefor, of a movable member for controL ling the tripping of the interrulner, and two watt clement-s connected to opposite terminals of the transformer for actuating the movable member equally in opposite directions under normal conditions.

t. The combination with a polyphasc translating device and a circuit interrupter tnerefor. of a differential watt relay operatively connected to the respective terminals of the translating device and adapted to be actuated to control the tripping of the interrupter only when a fault obtains in the translating device.

A differential relay comprising a shaft. two armatures mounted thereon, two watt elements for oppositely acting on each armature. and differentially-acting springs for normally maintaining the shaft in a predetermined position.

6. The combination with a polyphase transformer having different numbers of phases in its primary and secondary windings and a circuit interrupter therefor, of an induction relay comprising a movable member, oppositely acting watt elements therefor that are connected to the primary and the secondary windings. respectively, of the transformer, and means whereby the movable member controls the circuit interrupter.

7. In a polyphase circuit, the combination with a transformer and circuit interrupter-s for disconnecting the same from the circuit, of a single differential relay having opposing watt elements that are connected to the high and to the low-tension terminals. respectively, of the transformer to cause the interrimtcrs to be tripped only when a fault obtains in the transformer.

S. In a polyphase circuit, the combination with a translating device and circuit interrupters for entirely disconnecting the same from the circuit, of polyphase watt elements operatively connected to the respective terminals of the translating device, and a single movable member differentially acted upon by the watt elements to control the interrupters.

9. In an electric circuit, the combination with two circuit interrupteis for isolating a portion of the circuit, of two watt elements connected to the respective ends of that portion of the circuit to be protected, and a single means differentially acted on by the watt elements for controlling the interrupter-s.

10. In an electric circuit, the combination with two circuit interrupters for isolating a portion of the circuit, of a differential watt relay actuated in accordance with the difference of the power measured at each end of the portion of the circuit for controlling the tripping of the interrupters.

11. The combination with an electric circuit, of a differential watt relay actuated in accordance with the difference of the power measured at each end of a portion of the circuit, and means controlled by the watt relay for completely isolating that portion of the circuit when a fault obtains therein.

12. The combination with a transformer, of a differential watt relay actuated in accordance with the difference of the power measured at the primary and the secondary terminals of the transformer, and means controlled by the watt relay for isolating the transformer when a fault obtains therein.

13. The combination with a translating device and circuit interrupters therefor, of means responsive to the amount of the power input and to the amount of the power output, respectively, of the translating device, and mechanical means actuated in accordance with the difference of these two values for controlling the interrupters.

14. A protective relay for a translating de vice comprising an element responsive to the power of input of the device, an element responsive to the power output of the device and means controlled in accordance with the difference of the degrees of responsiveness of the two elements.

15. A protective relay for a translating device comprising an element responsive to the amount of the power input of the device, an element responsive to the amount of the power output of the device and means for operatively connecting the two elements.

16. A protective relay for a translating device comprising an element responsive to the power input of the device, an element responsive to the power output of the de vice and means responsive to the difference between the torques developed in the respective elements.

17. The method of protecting a translating device against aggravation of internal. faults which consists in energizing a movable element in accordance with the power input and another element in accordance with the power output and mechanically balancing the two elements to obtain the difference between the torques of the two elements for controlling the isolation of the translating device.

18. The method of protecting an electrical eneregy transformer from internal faults which consists in operatively connecting two watt relays to measure the power input and the power output, respectively, of the trans former and then employing the diiference between the torques developed in the relays for controlling the isolation of the transformer.

19. A differential relay comprising a shaft, two arinatures mounted thereon, two watt elements for oppositely acting on each armature, differentially-acting springs for normally maintaining the shaft in a predetermined position and means for adjusting the springs.

20. The method of obtaining differential protection for an electrical translating device without phasing out the various circuits to be connected which consists in connecting a plurality of devices to measure the power input and the power output, respectively, of the translating device and then balancing the measuring devices against each other.

In testimony whereof, I have hereunto subscribed my name this 19th day of Feby SEVERN D. SPR-ONG. 

